An electrical connector with connecting cable having a metallic coupling apparatus with a union nut, or with a screw and an inwardly-directed collar engaging a crimped sleeve, creating the connection between the coupling apparatus and the shielding of the connecting cable as known from DE 196 13 228 B4.
Producing a shielded plug connector having a crimped shielding sleeve is costly. Many individual components are needed, and preparing the cable to be connected is performed by hand, as is mounting the many individual components. In the case of plug connectors having an angulated shape, mastering the production is even more difficult. Establishing the electric connection by crimping components is, furthermore, not always safe; in particular, the contact resistance at the crimp connection may alter when the temperature changes, or with age, resulting in a reduction of the shielding quality of the plug connector. From U.S. Pat. No. 5,906,513, a shielded, molded electrical connector is known, wherein a sleeve-shaped, metallic housing having slits for forming tabs is provided on the side of the cable, and the tabs are pressed onto the metal braiding shielding of the cable. Thereafter, the sleeve-shaped metal housing is embedded with a thermoplastic material behind the metallic connection coupling, on the bared metal braiding shielding, and on the cable end. The thermoplastic material contains wire strands that are pressed against the sleeve-shaped metal housing during the molding process, establishing good electric continuity between the cable and the connector, or to the sleeve-shaped housing of plug connectors. Also here, the contact resistances between the shielding parts may degrade in case of temperature changes and with age.
From DE 10 2008 018 403 A1 and WO 2011/151373 A1, a plug connector with a shielded cable connected therewith is known. The connector has a molded, shielding sleeve made of electrically conductive material, in particular of electrically conductive plastics, and electrically connects the cable shielding to the coupling nut of the plug connector. A plastic filled with metal fibers is generally understood as electrically conductive plastic. Such electrically conductive material may be injection-moldable (see DIN 24450). In detail, the electric line ends of the cable are connected in the plug housing where a metal sleeve is arranged. Subsequently, an insulating carrier is injection molded, the carrier extending from the line shield into the housing. An electrically conductive sleeve part is injection-molded around the insulating carrier so as to connect the line shield with the metal sleeve and by doing so with the housing shield of the electrical connector. Electrically conductive plastics, however, establish only weak contacts with metallic surfaces of the plug connector or of the cable so that the contact resistance at the transition surfaces between the electrically conductive plastics material and the metallic surfaces at the plug connector or at the cable shielding shows increased values, which may further deteriorate if gaps or cracks occur due to the shrinkage or the melting of the plastics.
Furthermore, conductive plastics have a lower screening attenuation than full metal.